Obara T, Suzuki Y
Laboratory of Cell Differentiation, National Institute for Basic Biology, Okazaki City, Japan.
Dev Biol. 1988 Jun;127(2):384-91. doi: 10.1016/0012-1606(88)90325-9.
In vivo transcriptional activity of the Bombyx mori fibroin and sericin genes was estimated by nuclear run-on assay. Tissue-specific and developmental stage-specific expression of the fibroin and sericin genes through larval development was shown to be primarily regulated at the level of transcription. The expression patterns of these two genes are quite different in their developmental profile, suggesting that they are probably regulated by different underlying mechanisms. A finer spatial control of transcription could be found. The sericin gene transcription is mostly restricted to the posterior region of the middle silk gland throughout the fifth larval instar. Interestingly, the fibroin gene transcription is observed only in the anterior region of the posterior silk gland on the first day of the fifth instar, and spreads toward the posterior region as the fifth instar stage proceeds.
通过核运行分析估计了家蚕丝素基因和丝胶基因的体内转录活性。结果表明，在幼虫发育过程中，丝素基因和丝胶基因的组织特异性和发育阶段特异性表达主要在转录水平上受到调控。这两个基因的表达模式在发育过程中差异很大，表明它们可能受不同的潜在机制调控。可以发现转录存在更精细的空间控制。在整个五龄幼虫期，丝胶基因的转录大多局限于中部丝腺的后部区域。有趣的是，在五龄幼虫的第一天，仅在后部丝腺的前部区域观察到丝素基因的转录，并且随着五龄幼虫阶段的推进，转录向后部区域扩散。
